The present invention relates to a motor vehicle with a driver assistance system and a method of operating a driver assistance system.
The following discussion of related art is provided to assist the reader in understanding the advantages of the invention, and is not to be construed as an admission that this related art is prior art to this invention.
The automobile industry increasingly equips motor vehicle with a driver assistance system to assist the driver when exciting standard tasks, like parking or maintaining speed. In addition, systems are more and more in demand to enable autonomous driving. Driver assistance systems receive information from numerous detectors and cameras mounted to the vehicle. Images captured by the cameras are normally processed by an image processing device which generates processing results that are made available to the driver assistance system. A majority of image-processing algorithms is based on edge detection. Algorithms for edge detection are based on the recognition of sudden changes in color or brightness. Therefore, images need to be evenly illuminated when transmitted to an edge detection algorithm.
When employing such driver assistance systems in poor light conditions, the image area of the camera can be illuminated by lighting devices mounted on the vehicle. Since illumination from a vehicle is highly directed, the image may be distorted by shadows or intense contrasts. For example, sensitivity of the camera has to be reduced in the presence of reflecting or bright or close objects to avoid saturation. This, in turn, causes loss of sensitivity in darken image areas. Moreover, illumination of the vehicle surroundings, using a lighting device on the vehicle, may result in shadows which can be misinterpreted by the image processing device as edge.
It would therefore be desirable and advantageous to address this problem and to obviate other prior art shortcomings.